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Porsche Cayman GT4 Clubsport Build Overview

(2020 718 GT4 Clubsport โ€“ Track Day Edition)

If youโ€™ve followed Racer on Rails for a while, you already know our philosophy: take great cars, make them better, and then drive the hell out of them. This 2020 Porsche Cayman GT4 Clubsport Track Day Edition is the perfect example โ€” a factory-built Porsche Motorsports car with real pedigree and a second life that spans endurance racing, time attack, and driver development.

Before we go deeper, itโ€™s important to understand which Clubsport variant this is, because Porsche built several versions:


718 Cayman GT4 Clubsport Variants

Track Day Edition (This Car)

  • Designed for private owners and track day use
  • Same 425 hp 3.8L flat-six as Comp version
  • Lighter-duty fuel system
  • No air-jack system (but provisions exist)
  • Not homologated for GT4 racing

Competition Version (Not This Car)

  • Fully homologated for GT4 racing
  • Air-jack system included
  • Larger motorsport fuel cell
  • Endurance switches & safety electronics
  • Homologation restricts power/aero changes
  • Carbon and natural fiber material body panels

Newer 718 Cayman GT4 RS Clubsport

  • 4.0L RS-based platform
  • More power, higher RPM ceiling
  • Improved aero and suspension
  • The current model used in IMSA/SRO GT4
  • Much closer to a โ€œmini Cup Carโ€

Our car โ€” the Track Day Edition โ€” gives us the freedom to pursue more aero, more setup range, and more developmental headroom than the rules-restricted Competition version.


Where This GT4 Clubsport Came From

Photos of the car from its Ann Doherty era after arriving at RoR.

This GT4 Clubsport began its life with Ann Doherty, who ran it competitively in SCCA T1 and GT2 before upgrading to a 991.2 GT3 Cup Car.

Because the car came from Ann, we gained two major benefits:

  1. It had been maintained at a true professional standard.
  2. It had already proven itself at a national competition level.

When she moved to the Cup Car, we took ownership of the GT4 and immediately put it to work.


What We Used It For

1. Endurance Racing (2024)

Bombing down Turn 5 at Road America with World Racing League

The first chapter of this carโ€™s life with us was national-level endurance racing:

  • WRL Road America โ€” April 2024
    Our first outing. Strong pace, great aero learning, and flawless reliability.
  • ICSCC Cascade 8 Hours of Portland โ€” October 2024
    A full-day grind that gave us massive data on tire wear, pit strategy, and aero balance.

The car was consistent, predictable, and incredibly reliable โ€” exactly what you want in an endurance platform.


2. OnGrid Time Attack (2025)

With the Dundon Valkyrie aero package installed, the car moved into OnGrid GT+ and instantly became a serious contender.

Huge downforce. Big mid-corner speed. Better braking stability. It was a transformation.

Check out one of the flying laps from this past summer – matching 992 and 991.2 GT3 Cup car lap times!

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3. Driver Development & Testing Tool

This GT4 became one of our strongest tools for:

  • Advanced driver coaching
  • Back-to-back setup testing
  • Tire comparisons
  • Driver development beyond Spec E46, T3, and regional touring classes

Turnkey speed. Zero drama. Endless data.


Factory Specs โ€” 2020 Porsche Cayman GT4 Clubsport (Track Day Edition)

PHOTO SUGGESTION: Interior cockpit photo or engine bay shot.

Engine & Drivetrain

  • 3.8L naturally aspirated flat-six
  • 425 hp @ 7,500 RPM
  • 7-speed PDK w/ motorsport tuning
  • Motorsport cooling system
  • Mechanical LSD

Chassis & Safety

  • FIA welded cage
  • Motorsport wiring harness
  • Composite doors
  • Fire system
  • Air-jack provisions (air jack system not currently installed)
  • Recaro race seat + 6-point harness

Suspension & Brakes

  • 3-way MCS motorsport dampers (upgrade)
  • Fully adjustable alignment
  • Porsche Motorsport ABS
  • Motorsport stability control

Aero

  • GT4-spec splitter but currently running the full Dundon Motorsports Valkyrie Aero package (front splitter, canards, rear wing)
  • Adjustable rear wing
  • Factory Flat floor
  • Factory cooling and airflow optimization

Our Modifications & Upgrades

Dundon Motorsports Valkyrie Aero Package

  • Full-length carbon splitter
  • Functional multi-channel front diffuser
  • Canards
  • Swan-neck rear wing
  • High-efficiency rear diffuser

This fundamentally changes the carโ€™s downforce ceiling and high-speed stability.

Dundon Motorsports Valkyrie Aero front Bumpcer Canards in focus

Data & Electronics

  • AIM data integration
  • Radio/comms upgrades

Race Prep & Setup

  • Multiple alignment profiles
  • Corner balance for sprint, endurance, and time attack
  • Dundon headers/exhaust (optional configuration)
  • Tire mapping across A052, F200, and slicks

Deep Dive: Dundon Valkyrie Aero vs. Porsche Factory vs. Manthey Racing

Porsche Factory GT4 Aero

  • Designed to be predictable and safe
  • Built to meet strict GT4 regs
  • Limited splitter/wing/diffuser scope
  • Great for consistency but capped on downforce

Manthey Racing Aero

  • Refined airflow
  • Cleaner front-end efficiency
  • Slightly more downforce than OEM
  • Still constrained by GT4 rulebook

Dundon Valkyrie Aero

  • Not rule-limited
  • Significant downforce increase
  • Real front-end loading under trail braking
  • Balanced with a serious rear aero package
  • Center of pressure stability improves with speed

At The Ridge, the difference was dramatic: the car stopped washing out in the T3โ€“T4 transition and gained real front-end authority.


Real-World Lap Time Proof

This wasnโ€™t a pure A/B test โ€” different drivers, power levels, tires, and conditions โ€” but the result is hard to ignore.

June 2023 โ€” Homologated GT4 Aero @ Road America

  • Hoosier A7 (sprint tire)
  • Full GT4 power
  • Lap: 2:25.6

April 2024 โ€” Dundon Aero @ Road America

  • Yokohama A052 (endurance tire)
  • WRL power restrictions (ยพ intake blocked)
  • Full endurance fuel levels
  • Laps: Low 2:24s โ€” consistent

Less power.
Heavier car.
Slower tire.
Faster laps.

Conclusion:

The aero works. It transforms the platform. Check out this video comparison of the Dundon vs Manthay aero on the faster Cayman RS GT4.

YouTube player


What Types of Racing This Car Excels In

Endurance Racing (WRL, AER, ICSCC Enduros, ChampCar Pro)

  • Ultra-consistent
  • PDK-friendly
  • Great tire life
  • Zero drama across long stints

Time Attack (OnGrid, GTA, SCCA TT)

With Dundon aero?
Itโ€™s a legitimate GT+-class weapon.

Sprint Racing (SCCA ST, ICSCC ST/SPO, NASA ST1/ST2)

Great for drivers moving beyond grassroots or regional programs.

Driver Development

One of the best โ€œadvanced learningโ€ platforms weโ€™ve ever used.


Interested in Renting or Developing a GT4 Clubsport?

If youโ€™re curious what a Porsche Cayman GT4 Clubsport can do, weโ€™d love to help.

  • Want to rent this GT4 Clubsport for a race weekend or time attack?
    We offer full arrive-and-drive + coaching.
  • Already own a GT4 or Porsche race car?
    We can help you extract more from the car and yourself with setup, aero, maintenance, and coaching.

Reach out anytime. Letโ€™s build something fast together.

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Race Report 2: Circuit of the Americas SCCA Hoosier Super Tour

For the third year in a row, we headed back to Austin, Texas for the second round of the Hoosier Super Tour at the beautiful and challenging, Circuit of the Americas. Thankfully, we avoided the annual winter freeze that hits southern Texas and while it was dry all weekend, it wasn’t “warm” except for on load-in day (Thursday) and Sunday afternoon. Perfect! (Insert thick amounts of sarcasm)

Prior to the race weekend Jordan, Memo, Bryce and Mark flew into Houston, TX where we had the cars and trucks stored to whip the cars into shape. Can’t say enough how grateful we are to have friends across the country that have helped us with space to park and work on the cars. Thank you Todd Joseph Farley (TMJ Bimmers) and James Walker Jr!

Jordan taking a big swig of Green Redbull to do a full engine swap on the 81 SE46 that decided it just didn’t want to run anymore, at Sebring.

For this race report, we’re going to do something a little different. Driving at these bucket list tracks, we regularly get asked which track is our favorite, most unique, most scary and/or most challenging? So for this report, we’re going to focus a little more on what makes COTA such an awesome and challenging track to tackle.

1. COTA is Big!

At 3.426 Miles and 20 corners (using the Grand Prix layout), COTA is a long track with at least 20 opportunities to make a mistake and decent distances after a corner, so that you have ample time to relive and think about the mistake(s) you just made. All the while, watching your predictive lap timer reinforce, with math, that you made a mistake. ๐Ÿ™‚

The volume of corners in terms of learning the track is a challenge but to be perfectly honest, in the three years that we’ve come to the SCCA Hoosier Super Tour with now seven different drivers, not once have we had a discussion about “what corner comes next” or “the line” in terms of just getting around the track.

Each driver puts in the preparation work before the race weekend with time in a simulator, watching race videos and track walks – our drivers come to compete!

So “learning the track” isn’t a thing but another aspect of COTA that is a challenge is how wide the track is. This is a blessing and a curse. The track in general is wide enough to go three wide in multiple segments, which results in multiple lines that can be taken through a corner or sequence of corners. This gives us flexibility in racing conditions but it gives the same flexibility to competitors.

Ann Doherty in the #4 Porsche Cayman GT4 Clubsport trying to run away from a Touring 1 Camaro in the run to Turn 12

From the approach of turn 1 through the entry to the esses (turn 3) , it’s not just feasible but it’s common to see cars going 2 and 3 wide with only a marginal drop off in lap time.

Turn 6 is wide enough that it’s possible to attack another car from the outside, which then turns into the inside for Turn 7.

The entry into Turn 11 is like turn 1, almost an open runway with a lot of space to dive bomb into the corner but with the longest straight away on the tracking coming next, going two or three wide into turn 11, will punish your straight line speed down to turn 12. There are even lines to overtake someone on the outside in Turn 1, especially at the start of the races.

Turn 12 also is wide enough for at least two cars to go side by side and while not particularly fast, it’s possible and common throughout the weekend to see cars going side by side all the way until Turn 19.

Finally, Turn 20 can also easily allow two cars to go side by side but it will impact the exit speed and thus the time that runs all the way to turn 1.

2. COTA is technical. Really Technical.

Many tracks have some kind of bias due to the natural outcome of being “lap based” – e.g. at some point, the track will return back to start/finish. If a track has a clock-wise orientation, there will usually have more right hand corners than left hand corners. If a track is counter-clockwise (like COTA), vice-versa will be true.

So while COTA has a counter-clockwise orientation, it has exactly 10 left-hand corners and you guessed it, 10 right hand corners.

And yes, the three longest straight aways are setup by left-hand corners, which would normally make a team want to setup a car to be biased for left-hand corners BUT there are 6 different corners that are either high-commitment or high-duration (you spend a good amount of time in them), so it really pushes a team and driver to have a well balanced setup for both corner types, unlike what we’d for say Portland International Raceways or Lime Rock Park – pretty much all right hand corners.

COTA also has a wide variety of corners:

  • Short duration, slow speed and sharp angled corners: Slow corners make it really easy for drivers to over-slow on entry and if you don’t have the car pointed just right and at full throttle at the apex, the exit and the proceeding straight away suffer. Think the exit of Turn 1, Turn 11 and Turn 20 where the minimum speeds are in the mid to high 30’s depending on the car. Teams and drivers may be tempted to setup a car nice and loose on slow speed corners to get through these as quickly as possible but…
  • Medium/High-Speed Corners: Turn 3 (the entry into the esses), you enter near the top of 4th gear in the Spec E46’s (~105mph) and then need a well balanced car to carve through them.
  • Long duration medium speed corners: Turns 6 and the Carousel (turns 16 – 18) are both right hand corners where you are in them for longer than most corners. So how do you setup a car to both be awesome on slow quick corners but not too skaty through carousel type corners?
  • COTA beats up cars: Remember in 2019 when Sebastian Vettel had a suspension arm break on the exit of a corner? That’s from the bumps that form and change all the time from the ground/earth under the pavement. The dirt on which COTA sits isn’t super stable to begin with due to how dry the area typically is but then when it rains, it RAINS – think flash flooding. COTA has been repaved multiple times and it was repaved in time for the 2022 season (we were there) but in that one single year, the track has gone from a pretty smooth pavement, to having bumps all over the track.
  • Some notable bumps exist in the braking for Turn 1, throughout Turn 6, the exit of Turn 9, breaking for Turn 11 and right as you confidently exit the carousel of Turn 18, there is a healthy sized bumped waiting to knock you off your high horse, when you get too confident.
    • Finally, COTA has lots of FIA curbs, of which in the dry are awesome and to be used as much as possible but the repercussion is that the vibrations from curb usage travel all through the suspension and chassis, leading to increase amounts of brake pad knock-back and as I personally found in 2021, damaged suspension components. Expect to do a deep inspection of your wheel bearings, control arms, shocks and a full nut and bolt.
Thad Berger in his Spec E46, looking where he wants to go and hitting those apexes as hard as he can.

3. COTA is ROUGH!

Remember in 2019 when Sebastian Vettel had a suspension arm break on the exit of a corner? That’s from the bumps that form and change all the time from the ground/earth under the pavement. The dirt on which COTA sits isn’t super stable to begin with due to how dry the area typically is but then when it rains, it RAINS – think flash flooding. COTA has been repaved multiple times and it was repaved in time for the 2022 season (we were there) but in that one single year, the track has gone from a pretty smooth pavement, to having bumps all over the track.

Some notable bumps exist in the braking for Turn 1, throughout Turn 6, the exit of Turn 9, breaking for Turn 11 and right as you confidently exit the carousel of Turn 18, there is a healthy sized bumped waiting to knock you off your high horse, when you get too confident.

Finally, COTA has lots of FIA curbs, of which in the dry are awesome and to be used as much as possible but the repercussion is that the vibrations from curb usage travel all through the suspension and chassis, leading to increase amounts of brake pad knock-back and as I personally found in 2021, damaged suspension components. Expect to do a deep inspection of your wheel bearings, control arms, shocks and a full nut and bolt.

So, how did we do?

Ann Doherty was at COTA for the second time, having done the Hoosier Super Tour in 2022 as well and not only did she improve on her personal best lap times from a year ago, despite the track being in worst shape but she continued her streak of finishing right behind some experienced and very accomplished drivers! The raw pace is there, she’s getting faster and now we shift our focus to a little more on race craft as on the Sunday race, she lost positions on the start and got stuck behind a group of slower cars (in and out of class) and with a couple laps left in the race, she turned it up and got past them all.

Ann also showed serious grit as she got hit decently hard in race 1, lap 1 and turn 1! With a car that had a bent suspension and rear bumper falling off, she finished the race. We got the car put back together the best we could and she finished P5 but with lap times towards the end that would have been in contention for P2 and P3. Awesome job!

Thad Berger not just raced but drove COTA for the very first time at this race weekend! He made solid progress throughout the weekend, improving on just about every session and by the end of the day on Sunday, he was solidly in the mid-pack (P8 out of 13) and battling with MX-5 Global Cup cars and 350Z’s!

Simon Asselin had another busy weekend, doing double duty in his Touring 3 Spec E46 and GT2 Porsche GT3 Cup Car. In Touring 3, he finished P4 in race 1 and P3 in race 2 with AMAZING battles the entirety of both races. Check out his race video below!

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In GT2, Simon was busy as well! He started from the back in Race 1 as a cone ended up destroying one of his front tires on the outlap but made his way through to P8 and in race 2, he continued his march forward and ended up P3 for two podiums throughout the weekend. Great job, Simon!

Dave Orem had to last minute pull out of the race weekend due to a family situation but we ran his car during the test day and it was a ripper! Dave will be back for Road Atlanta!

Thank you to the entire team who is behind the scenes and making it all happen! Memo Calderon, Bryce Allen, Jordan Allen, Reid Morris, Tyer Mayer, Tyler Campbell, Mark Farmer, Harry Mineer and our amazing coaches, Seth Thomas and Ray Phillips!